This aerial photo shows the wreckage of Asiana Airlines Flight 214 after it crashed July 6 at San Francisco International Airport. / Marcio Jose Sanchez, AP

by Charisse Jones and Bart Jansen, USA TODAY

by Charisse Jones and Bart Jansen, USA TODAY

The experience of the pilot at the controls of Asiana Airlines Flight 214 could be a factor in the investigation of Saturday's crash of the Boeing 777, according to federal crash investigators.

Lee Gang Guk had spent just 43 hours flying the 777, and was accompanied by a deputy pilot more familiar with the jet to assist him, according toAsiana Airlines.

By U.S. standards, Lee's limited time flying a 777 would have also likely required him to have a more experienced peer in the cockpit. Generally, when a pilot has been flying a new jet for roughly 100 hours or less, they must have either a more experienced captain or co-pilot present to observe, guide, or help them, said Kit Darby, a former United Airlines pilot who now provides simulator training.

There were three other pilots on board Asiana Airlines Flight 214, including the deputy pilot Lee Jeong Min, who had spent 3,220 hours flying 777s, according to the Associated Press, quoting the Ministry of Land, Infrastructure and Transport in South Korea.

Although Lee was a newcomer to the 777, he had clocked nearly 10,000 hours piloting a variety of other jets.

"He wasn't a novice,'' said Les Westbrooks, a former commercial airline pilot who is an associate professor of aeronautical science at Embry-Riddle Aeronautical University in Daytona Beach, Fla. "He was new to this particular plane, but he was a very experienced pilot.''

Federal crash investigators were to speak to the pilots Monday as part of the inquiry into why the Asiana crash occurred, leaving two dead and scores injured.

Deborah Hersman, chairwoman of the National Transportation Safety Board, was asked about the pilot's experience on different aircraft and his transition to the 777, but she said she didn't want to influence the interviews with the flight crew.

"We don't want to influence the responses," she said at a news briefing Monday. Those interviews are expected to give investigators a clearer picture of what was going on inside the cockpit and how they were reacting.

NTSB officials said that the ill-fated flight slowed far more than the pilot intended before crashing, but it's not clear yet from the flight-data recorder how the speed affected the plane's descent into San Francisco International Airport.

Pilots disengaged the autopilot when the Boeing 777 was 1,600 feet in the air, about 82 seconds before the crash Saturday, according to Hersman.

She had previously indicated from the cockpit voice recording that at seven seconds from impact, the crew recognized their speed was slow; at four seconds, equipment sounded an alarm warning of the potential to stall; and at 1.5 seconds, a crewmember said to abort the landing and circle the airport for another try.

At three seconds before impact, the plane reached its lowest speed of 103 knots, with engine power increasing, and it crashed at 106 knots, Hersman said.

"This aircraft was significantly slower than their target approach speed of 137 knots," which is the speed they wanted to reach the end of the runway, Hersman said.

Westbrooks said that landing too slow is an error that pilots learn from their first flying lesson to try to avoid.

"It is the most fundamental thing that you learn in flying . . . to not get slow like this,'' Westbrooks said. "Once we get real slow, the flow of the air over the wings starts to break apart, and it doesn't flow over smoothly, and we start losing our lift.''

Darby said that the dramatic slowdown may have resulted from the pilot trying to correct himself.

"He probably started high and fast and ended up . . too low and slow,'' Darby said.

Saturday's accident occurred during Lee Gang Guk's first time landing a 777 at San Francisco International Airport, according to Asiana Airlines.

Darby said that some airports require special training, for instance if the pilot has to navigate mountainous terrain. Although San Francisco doesn't fall into that category, Darby said there were some characteristics and circumstances that might have made landing more difficult.

"There are some things about San Francisco that make it demanding,'' Darby said. Flying over water as you approach can make it harder for pilots to get a feel for how fast they're going, he said.

Also, on Saturday, the "glide slope" or radio beam that electronically helps an airplane descend at the proper angle wasn't available. Incoming planes would have been made aware of that, Darby said, and an alternate guide visible through the cockpit window would have sufficed.

Nevertheless, he said, "the combination of that missing beam and coming in over the water is a real risky combination.''

As the investigation continues, Westbrooks cautioned that there is seldom a single misstep or malfunction that causes a plane crash.

"Not just one thing happens,'' he said. "It's a chain of events that build up to it.''